Standing seam metal roofs are often employed in roofing applications where protection and durability are paramount. They are most commonly employed on agricultural buildings, such as barns or other farm outbuildings, or on commercial buildings, such as restaurants. Standing seam metal roofs are thus typically referred to as “commercial roofing,” “agricultural panel roofing,” or “barn roofing.” However, premium “standing seam” metal roofs often see use in residential applications.
These types of metal panel roofs are made up of narrow panels that run vertically up the roof, typically placed over a plywood or particle board substructure. These panels include raised edges running along each of the left and the right sides of the panel. To install the roof, the raised edge of each panel is placed alongside the opposite raised edge of the adjoining panel, and the panels are then coupled together by crimping or bending of the raised edges. This creates the most prominent visual features of a “standing seam” metal roof: the raised interlocking seams that are created when one panel is joined to the next.
These seams serve to create a seal between one panel and the next, preventing rainwater or other fluid from leaking through the roofing panels and seeping into the roofing substructure below the roofing panels, as well as to the area between each roofing panel. Typically, such leakage is undesirable because it leads to the substructure of the roof becoming rotted or otherwise losing structural integrity, or because it leads to visible leaks within the building.
One problem with standing seam metal roofs is that snow accumulating on them may fall in large masses. For example, heat rising from the building may melt the bottom layer of snow and slicken the interface between the accumulated snow and the metal roof, causing a significant quantity of snow to slide off all at once. This can potentially cause damage to people or property in the path of the snow.
As such, snow guards are often installed on standing seam metal roofs. These act to prevent snow from falling off of the metal roof, thereby preventing damage to people or property that might be caused by falling snow. Snow guards can be coupled to either a roofing panel of the metal roof or to the seam of the abutting roofing panels.
In the prior art, it has been found that it is undesirable to secure snow guards to standing seam metal roofs by the use of screws or bolts. This is because screws and bolts can puncture the roofing panel or seam into which they are driven, destroying the hermeticity of the metal roof, such that it no longer keeps out fluid. This enables fluid to seep into the underlying roof substructure, causing all of the attendant problems discussed above. See, for example, U.S. Pat. No. 6,834,466, “Snow Guard,” issued to Trevorrow et al.
As such, attachment mechanisms for snow guards have most commonly been clamps that fit to either side of a standing seam. These clamps, however, have their own problems. Often, in order to attach firmly to the roof, the clamps act to bend or crimp the standing seam, creating a discontinuous portion, in order to prevent the clamp from sliding on the standing seam. Such bent standing seams can appear unsightly. When the snow guard is employed in an agricultural or commercial building, such as a barn, this is often less of a problem; barns and similar buildings often make use of standing seam metal roofs because of the low price or because of the protection they offer, and the aesthetics of the roof are less important. However, as mentioned, standing seam metal roofs have been seeing increasing use on residential homes, and in such applications aesthetics are typically more important.
Alternatively, the clamps used to attach the snow guard to the standing seam can be looser. However, this creates or exacerbates other problems. For example, in many cases, it may be desired to perform repairs or maintenance work on the standing seam metal roof, which may require the erection of scaffolding on the roof so that workers can access the part of the roof that needs to be repaired. It is usually desirable to couple the scaffolding to fixtures on the roof. However, a snow guard supported by a clamp system—and particularly a clamp system that is designed to clamp loosely—is not likely to offer sufficient strength to support scaffolding. This means that a snow guard that relies on a clamping system to anchor it to a standing seam metal roof may not be able to support scaffolding, and may even have to be removed in order to put the scaffolding in place.
The installation of a snow guard that makes use of any kind of clamps can also have aesthetic downsides above and apart from any aesthetic damage that may be inflicted on the roof. In most cases, the clamps will not aesthetically blend into the rest of the roof system; the thin, clean lines of the standing seams of the roof will be interrupted by the blocky nodules of the clamps used to support the snow guard, creating an undesirable visual effect.